The goal of this dissertation was to contribute to our understanding of the relationship between supply chain structure and the pursuit of a sustainability-driven corporate strategy. The literature indicates that in order to pursue a sustainability-focused strategy, an increased level of integration across the supply chain is required. However, there are also industry-level dynamics that impact observed levels of vertical integration. That is, some industries are naturally more integrated than others based on the maturity level of the industry. Thus, some firms may experience opposing forces regarding their sourcing strategies once they choose to pursue a sustainability-focused strategy. To explore this potential tension, it is first necessary to objectively measure vertical integration. Several methods for measuring vertical integration exist; however, all of these methods rely exclusively on economic data. These measures might overlook other forms of integration that might be enacted, such as the development of stronger social ties. Thus, this research will seek to utilize a novel method that makes use of social network analysis to assess integration among firms in a supply chain along social dimensions. This dissertation 1) determined the correlation between having a vertically-integrated organizational structure and pursuing a sustainable supply chain strategy by identifying if sustainability-focused companies (SFCs) have a more vertically-integrated organizational structure than their counterparts that are not pursuing such strategies, 2) examined the evolution of supply chain structure as a company becomes more environmentally, economically, and socially sustainable over time, and 3) defined the social ties between SFCs and their first- and second-tier suppliers to understand if they develop stronger social ties as a potential substitute for pure vertical integration. This dissertation is comprised of four main parts. In the first part of the dissertation, I compared three recently developed vertical integration indices based on consistency and ease of measurement. The three vertical integration indices studied were empirically tested on companies in the U.S. Medical Devices Industry and the limitations of each are discussed. Our analysis suggested adoption of the Fan and Lang's method. In the second part, I examined the vertical integration level of environmentally sustainable and non-sustainable companies. I empirically examined the vertical integration level of 144 sustainability-focused companies in 9 different industries. The results demonstrate that sustainability-focused companies in the Medical Devices Industry and the Industrials Industry tend to have more vertically integrated organizational structures than their industry competitors that are not pursuing such a strategy since these two industries are production oriented and they have closer relationships with their suppliers. In the third part, the objective was to understand how the organizational structure of sustainability-focused companies changes over time as the companies become more environmentally, economically, and socially sustainable. I applied trend analysis to the sustainability and vertical integration level of the companies. Our sample consisted of 10 sustainability-focused companies from the industrials industry. I used the content analysis of annual reports to calculate sustainability development scores, and applied the Fan and Lang's method to determine the vertical integration level of the companies. The study results demonstrated an increasing trend in both vertical integration and sustainability development of industrial industry companies over a 15-year of period. Furthermore, the companies became more vertically integrated as their environmental, economical, and social sustainability increased. Finally, in the fourth part, I developed and empirically tested a theoretical model that examines the supplier relationships of sustainability-focused companies (SFCs) to understand if these relationships are substitute to a vertically integrated organizational structure. Furthermore, I tested if SFCs are more socially connected to their suppliers compared to non-sustainable companies (non-SFCs). An online survey instrument was utilized for data collection. The empirical findings of path analysis demonstrated that SFCs establish long term relationships, collaborate, transfer know-how and experience, and create strong-ties with their first and second-tier suppliers to have an organizational structure that is substitute to a pure vertical integration. Findings further revealed that SFCs are connected to their first and second tier suppliers with stronger social ties compared to non-SFCs. Results support the natural transaction cost economics and natural resource based perspectives. Our study results should be useful to researchers and managers who are interested in corporate sustainability behavior.

<p>The Table Mountain Group (TMG) Formation is the lowest member of the Cape Supergroup which consists of sediments deposited from early Ordovician to early Carboniferous times, approximately between 500 and 340 million years ago. The Table Mountain Group (TMG) aquifer system is&nbsp / exposed along the west and south coasts of South Africa. It is a regional fractured rock aquifer that has become a major source of bulk water supply to&nbsp / meet the agricultural and urban water requirements of the Western and Eastern Cape Provinces of South Africa. The TMG aquifer system comprises of an approximately 4000 m thick sequence of quartz arenite and minor shale layers deposited in a shallow, but extensive, predominantly eastwest striking&nbsp / asin, changing to a northwest orientation at the west coast. The medium to coarse grain size and relative purity of some of the quartz arenites,&nbsp / together with their well indurated nature and fracturing due to folding and faulting in the fold belt, enhance both the quality of the groundwater and its&nbsp / exploitation potential for agricultural and domestic water supply purposes and its hot springs for recreation. The region is also home to some unique&nbsp / and indigenous floral species (fynbos) of worldwide importance. These and other groundwater dependent vegetation are found on the series of&nbsp / mountains, mountain slopes and valleys in the Cape Peninsula. The hydrogeology of the TMG consists of intermontane and coastal domains which&nbsp / have different properties but are interconnected. The former is characterized by direct recharge from rain and snow melt, deep groundwater circulation with hot springs and low conductivity groundwater. The coastal domain is characterized by shallow groundwater occurrence usually with moderate to&nbsp / poor quality, indirect recharge from rainfall of shallow circulation and where springs occur they are usually cold. The sustainable utilization of the TMG&nbsp / aquifer addressed the issues of the groundwater flow dynamics, recharge and discharge to and from the aquifer / challenges of climate change and climate variability and their potential impact on the aquifer system. The concept of safe yield, recharge and the capture principle and the integration of&nbsp / sustainable yield provided the basis for sustainable utilization with the adaptive management approach. Methodology used included the evaluation of&nbsp / recharge methods and estimates in the TMG aquifer and a GIS based water balance recharge estimation. The evaluation of natural discharges and&nbsp / artificial abstractions from the TMG aquifer system as well as its potential for future development. The Mann-Kendal trend analysis was used to test historical and present records of temperature and rainfall for significant trends as indication for climate variability and change. The determination of&nbsp / variability index of rainfall and standard precipitation index were additional analyses to investigate variability. The use of a case study from the Klein&nbsp / (Little) Karoo Rural Water Supply Scheme (KKRWSS) within the TMG study area was a test case to assess the sustainable utilization of TMG aquifers.&nbsp / Results show that recharge varies in time and space between 1% and 55% of MAP as a result of different hydrostratigraphic units of the TMG based on&nbsp / geology, hydrology, climate, soil, vegetation and landuse patterns however, the average recharge is from 1% to 5% of MAP. The TMG receives recharge&nbsp / mainly through its 37,000 km2 of outcrop largely exposed on mountainous terrain. Natural discharges from the TMG include 11 thermal and numerous&nbsp / cold spring discharges, baseflow to streams and reservoirs, and seepage to the ocean. Results from this study also show increasing temperature&nbsp / trend over the years while rainfall trend generally&nbsp / remain unchanged in the study area. Rainfall variability persists hence the potential for floodsand droughts in the region remain. Global and Regional Models predict about 10% to 25% reduction in rainfall and increase in variability in future. Impacts of&nbsp / his change in climate will affect the different types of aquifers in various ways. Increase in temperature and reduction in rainfall will increase&nbsp / evapotranspiration, reduce surface flows and eventually reduce shallow aquifer resources. Coastal aquifers risk upsurge in salinisation from sea level&nbsp / rise and increase in abstractions from dwindling surface water resources. While floods increase the risk of contamination to shallow aquifers droughts&nbsp / put pressure on all aquifers especially deep aquifers which are considered to be more reliable due to the fact that they are far removed from surface conditions. Future population growth and increase in freshwater demand will put more pressure on groundwater. Recharge to groundwater have been&nbsp / over-estimated in certain areas in the past leading to high abstraction rates from boreholes causing extensive groundwater storage depletion evident by high decline in groundwater levels in these areas and hampering sustainable management of the aquifer resources. Over-abstraction have resulted in&nbsp / loss of stream flow and baseflow reduction to streams during summer, complete loss of springs and reduction of flow to others. Flow to wetlands,&nbsp / riparian vegetation, and sometimes loss and shifts in dependent ecosystems have also resulted from over-abstraction. Sustainability has spatial and&nbsp / temporal implications due to changing climate and demand. The study recommends adaptive management practices in which several factors are&nbsp / considered in managing groundwater together with surface water resources in order to maintain ecological and environmental integrity. The KKRWSS&nbsp / and other groundwater supply schemes in the Western and Eastern Cape Provinces demonstrate the huge potential of the TMG to provide freshwatersupply for domestic and irrigation water needs however, the huge decline in groundwater levels due to over-abstraction in the KKRWSS and&nbsp / other groundwater schemes underscores the need for sustainable utilization of the TMG groundwater resources for present and future generations with&nbsp / minimal impacts on the quality, dependent hydrological and ecosystems as well as the environment.</p>

This study is concerned with developing a model to identify small-medium U.K. companies at risk of financial failure up to five years in advance. The importance of small companies in an economy, the impact of their failures, and the lack of failure research with respect to . this population, provided justification for this study. The research was undertaken in two stages. The first stage included a detailed description and discussion of the nature and role of small business in the UK economy, heir relevance, problems and Government involvement in this sector, together with literature review and assessment of past research relevant to this study. The second stage was involved with construction of the models using multiple discriminant analysis, applied to published accountancy data for two groups of failed and nonfailed companies. The later stage was performed in three parts : (1) evaluating five discriminant models for each of five years prior to failure; (2) testing the performance of each of the .five models over time on data not used . in their construction; (3) testing the discriminant models on a validation sample. The purpose was to establish the "best" discriminant model. "Best" was determined according to classification ability of the model and interpretation of variables. Finally a model comprising seven financial ratios measuring four aspects of a company's financial profile, such as profitability, gearing, capital turnover and liquidity was chosen. The model has shown to be a valid tool for predicting companies' health up to five years in advance.

Measurement of chemical composition of precipitation is important both to understand acidification of terrestrial and aquatic ecosystems and neutralization process in the atmosphere. Such data are scarce in the Mediterranean region. In this study, chemical composition of daily, wet-only, 387 number of rain water samples collected between 1991 and 1999 were investigated to determine levels, temporal variation and long-term trends in concentrations of major ions and trace elements between 1991 and 1999. Samples had already been collected and some of the analysis had been completed. The anions SO42-, NO3- and Cl- were analyzed by HPLC coupled with UV-VIS detector, NH4+ was analyzed by colorimetry and H+ ion was analyzed by pH meter. The major ions and trace metals were analyzed by using Atomic Absorption Spectrometry (AAS) and Graphite Furnace Atomic Absorption Spectrometry (GFAAS). In this study complete data set were generated by analyzing samples that had not been previously analyzed for major ions and trace elements with Inductively Coupled Plasma with Optical Emission Spectrometry (ICP-OES). Statistical tools were used to determine the distribution of the pollutants. The rain water data tends to be log-normally distributed since data show large variations due to meteorological conditions, physical and chemical transformations and air mass transport patterns. The median pH of the rain water was found to be 5.29, which indicates that the rain water is not strongly acidic. This case is not a result of lacking of acidic compounds but rather indicates extended neutralization process in rain water. Eastern Mediterranean atmosphere is under the influence of three general source types: (1) anthropogenic sources, which are located to the north and northwest of the basin brings low pH values to the region (SO42-, NO3- ions) / (2) a strong crustal source, which is dried and suspended local soil and air masses transported from North Africa transport which have high pH values (Ca2+, Al, Fe ions) and (3) a marine source, which is the Mediterranean Sea itself (Na+, Cl- ions). In the region, the main acid forming compounds are H2SO4 and HNO3 whereas / CaCO3 and NH3 are responsible for the neutralization process. To describe the level of pollutant concentrations and the factors that affect their variations in rain water / ion compositions, neutralization of acidity, short and long-term variability of ions and elements, their time trend analysis and wet deposition fluxes were investigated briefly. Positive matrix factorization (PMF) was used to determine components of ionic mass in the precipitation. In Antalya Station the rain water has five factors: free acidity factor, crustal factor, marine factor, NO3- factor and SO42- factor. Potential Source Contribution Function (PSCF) and trajectory statistics were used to determine source regions generating these components. NO3- has potential source regions of Western Mediterranean countries and North Africa, whereas SO42- has additional southeasterly trajectory components of Israel and south east of Turkey.

The main objective of this work is to evaluate the dependency of the price of beef in the income of households. For the six selected EU will be examined twelve consecutive period from 2001 to 2012 will be used for the calculation of trend analysis, the coefficient of elasticity and correlation index. On the basis of these results was to confirm that the four selected countries dependence prices of beef in the income of households. These states are the Czech Republic, Slovakia, Germany and Austria. In Poland and Hungary dependence was refuted.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Dados sedimentológicos e hidrodinâmicos foram utilizados para estudar a dinâmica sedimentar da margem interna da restinga da Marambaia (baía de Sepetiba, Rio de Janeiro, SE Brasil). Foram realizadas três campanhas amostrais para coleta de sedimentos ao longo da restinga da Marambaia e na área submersa adjacente. Adicionalmente, em dezembro de 2013, três fundeios simultâneos para aquisição de dados hidrodinâmicos foram conduzidos paralelamente à restinga, ao longo da profundidade média de 6,5 metros. As medições abrangeram dois ciclos de maré (25 horas), incluindo perfilagem com CTDs, perfilagem correntométrica e coleta de amostras de água para determinação das concentrações do material particulado em suspensão. A partir do processamento das amostras de sedimentos em laboratório, foram obtidos os parâmetros estatísticos (média, desvio-padrão e assimetria) para o detalhamento da caracterização sedimentológica da área de estudo, bem como a aplicação de um modelo de tendência direcional de transporte de sedimentos (GisedTrend). A restinga apresenta areias médias e bem selecionadas, enquanto as amostras coletadas na porção submersa, em profundidades maiores que 2 m, passam de areias finas e bem selecionadas a siltes finos e mal selecionados em maiores profundidades. Quatro casos de tendência de transporte foram explorados em um total de 14 possibilidades e os mais significativos foram analisados com o intuito de identificar áreas de acumulação e remoção de sedimentos, podendo estar associados aos processos responsáveis pelo transporte de sedimentos, tais como correntes geradas pelos ventos locais, marés e dispersão de plumas de sedimentos em suspensão. Os dados hidrodinâmicos, durante o período amostrado, permitiram observar o complexo padrão de circulação existente, especialmente na área adjacente à área central da restinga. Dentre as observações realizadas, verificou-se a ocorrência de assimetria da maré, fato já documentado em trabalhos anteriores conduzidos próximo ao principal canal de acesso à baia, com períodos de enchente mais curtos e períodos de vazante mais longos. Diferentemente do que foi reportado nestes trabalhos, os períodos de vazante foram associados às correntes de maior intensidade. As concentrações de material particulado em suspensão situaram-se, em média, entre 10 e 20 mg/L tanto em superfície como próximo ao fundo; no entanto, suas variações temporais não apresentaram qualquer relação com as fases da maré. Possíveis áreas de convergência e divergência da circulação / células de transporte de sedimentos foram identificadas e comparadas aos vetores de tendência de transporte obtidos através do modelo GisedTrend, com resultados satisfatórios. / Sedimentological and hydrodynamic data sets have been used to study the sediment dynamics along the Marambaia barrier island bayside shoreline (Sepetiba bay, Rio de Janeiro state, SE Brazil). Three sampling campaigns were carried out to collect surface sediment samples along the barrier island and on the nearby submersed area. Additionally, in December 2013, hydrodynamic measurements were simultaneously conducted at three anchor stations positioned parallel to the barrier island, roughly along the 6.5 m isobath. The measurements, that spanned two full tidal cycles (25 hours), included water column profiling with CTDs, water column current profiling, and water column sampling to determine suspended-sediment concentrations. Once the sediment samples had been processed in the laboratory, statistical parameters (mean, sorting and skewness) were computed, allowing the thoroughful sedimentological characterization of the study area as well as the application of a grain-size trend analysis model (GisedTrend) to determine sediment transport trend vectors. The barrier island is chiefly made up of medium, well-sorted sands grading to fine, well-sorted sands and fine, poorly-sorted silts at greater depths. Four trend cases out of the 14 possibilities were explored and the most significant were further analyzed in order to identify areas of sediment accumulation or removal, and then be associated with the possible physical processes responsible for sediment transport, such as tidal currents, wind-generated currents and dispersal of sediment plumes. Hydrodynamic data documented that, over the time scale of the measurements, the water column circulation is highly complex, especially in the area adjacent to the center of the barrier island. As already verified in the area close to the main navigational channel, tidal asymmetry was documented, with floods being shorter than ebbs. However, contrarily to these previous observations, ebb currents were stronger than flood currents. Mean suspended-sediment concentrations (SSC) ranged between 10 and 20 mg/L both close to the surface and the nearbed area; yet, no relationship between SSC temporal variability and tidal stage could be identified. Possible convergence and divergence circulation / sediment transport cells were identified and compared to the GisedTrend output, with satisfactory results.

In the present work, methodology of statistical analysis of change evolved by Kundzewicz and Robson (204) is revised to obtain a robust methodology named as “Comprehensive Aproach” which addresses research gaps of earlier method, as also those found by literature review. Main aspects of the revised method are: 1) importance of graphical representations as first step, in which, if line spectrum has constant spectral density function then time series is random and no need of further trend detection, 2) importance of computation of statistical parameters of data for deciding type of step change test to be used and for cross checking results of exploratory data analysis (EDA), 3) application of EDA, statistical parameters and checking assumption(s) about the data by statistical test(s) is suggested and also results of these steps can be used to cross check results of each other, 4) suggested basis for selection of step change test(s) i.e. evaluation of two aspects of step change viz. detection and location of step change, 5) suggested basis for selection of trend detection tests i.e. evaluation of all four aspects of trend viz. magnitude, statistical significance, beginning and end of trend and nature of trend, 6) evaluation of regional significance is suggested as essential wherever applicable. The revised method i.e. “Comprehensive Approach” is applied for the trend detection of rainfall of seven homogenous rainfall regions and al India at annual, monthly and seasonal temporal scales for three time periods 1901-203, 1948-203 and 1970-203. Between 100 N to 300 N, there was marked increase in precipitation from 190 to 1950s, but decrease after about 1970 (Trenberth et al., 207). Thus starting years of three time periods are selected as 1901, 1948 and 1970. To have similarity of end year, in analysis periods given in chapters 1, 2 and chapters 3, 4; their end years are kept close to each other i.e. end year of analysis periods is 203 in chapters 1, 2 and end year of analysis periods is 204 in chapters 3, 4. Thus 203 are considered as common end year of three time periods. Burn and Elnur (202) sugested that least number of years required for ensuring statistical validity of results of trend detection are 25 years. So in the third time period (1970-203), the duration is 34 years which is more than 25 years. Three time periods are having data of 103 years (1901-203), 56 years (1948-203) and 34 years (1970- 203) so effect of different time durations on trend detection analysis results is studied. Also temporal scales used in trend detection analysis are annual, monthly and seasonal (4 seasons) thus presence of trend is assessed in these main temporal scales. Results of the analysis showed that, statistically significant trends are found in: 1) winter rainfall time series of peninsular India (PENIN) region for the time period 1901-203, 2) pre-monsoon rainfall time series of north west India (NWIND) and central north east India (CNEIN) regions for the time period 1948-203, 3) monsoon rainfall time series of west central India (WCIND) region for the time period 1948-203, 4) August month rainfall time series of north east India (NEIND) region for the time period 1901-203, 5) June month rainfall time series of NEIND region for the time period 1948-203, 6) Also regionally significant trends are detected in pre- monsoon rainfall time series of five homogeneous regions for the time period 1948-203. Regionally significant trends are detected in pre-monsoon rainfall time series of five homogeneous regions for the time period 1948-203. But effect of cross correlation between rainfall time series of stations of subdivisions and between the sub-divisions in a region is not accounted in the field/regional significance evaluation and Hegel et al. (207) suggested that reactions to external forcing in trends of regional precipitation trends exhibit weak signal to noise ratios and likely to exhibit strong variations in space because of dependency of precipitation on geographic parameters like pornography and atmospheric circulation. Thus attribution of precipitation is more difficult. Also Saikranthi et al. (2013) suggested that homogeneity of rainfall zones may change in future. So, attribution of trends detected in pre-monsoon rainfall time series of five homogeneous regions was not possible. The results of statistically significant trends are confirmed by smoothing curves, innovative trend analysis plots and Sen.’s slope estimates. Contributions by present trend detection study on rainfall of homogenous regions by using “Comprehensive Approach” method are: 1) modification of guidelines of statistical analysis of change to evolve a robust method termed as “Comprehensive Approach”, 2) systematic trend detection analysis is performed pertaining to the rainfall of core monsoon India (CORIN) region and homogeneous India (HOMIN) region, which was not done earlier, 3) systematic trend detection analysis is performed on the rainfall of al India and seven homogenous regions concurrently for aforesaid temporal scales and time periods (except regional significance evaluation only for five homogeneous regions), which was not done earlier, 4) Man Kendal test with block bootstrapping approach (MKBBS) test (not effected by serial correlation) is used for trend detection of serially correlated data and Man Kendal (MK) test is used for trend detection of serially uncorrelated data. Sen.’s slope is used for evaluation of trend magnitude, 5) evaluation of field/regional significance of trends in rainfall over five homogenous regions is performed, which was not done earlier, 6) Location of beginning, end and progress of trend in rainfall of all India and seven homogenous regions concurrently is performed, which was not done earlier. As mentioned aforesaid, attribution of regionally significant trends detected in pre-monsoon rainfall time series of five homogeneous regions for the time period 1948-203 was not possible because of non-accounting of effects of cross correlation, attribution of rainfall is difficult and homogeneity of rainfall zones may change in future as discussed above in detail. So a thorough investigation about trends in rainfall, three temperatures (minimum, mean and maximum) and stream flow at regional (basin) scale was proposed to be ascertained. As Tapi basin is exposed to occurrence of heavy floods (Joshi and Shah, 2014) and it is climatically sensitive (Bhamare and Agone, 201; Gosain et al. 206; Deshpande et al., 2016), it is considered as study area. The trend detection analysis of gridded data (chapter 4) and regional time series (chapter 3) of rainfall and three temperatures data (1971-204) along with that for station data of stream flow (1979-204) of five gauging stations (chapter 4) is carried out using “Comprehensive Approach” for all temporal scales. Common available end year of data of rainfall, temperature and stream flow was 204 as data after 204 was not available for stream flow for all five gauging stations. Also data of rainfall (0.50 x 0.50) was available from year 1971, which was common starting year among data of rainfall and three temperatures. Also common starting year of stream flow data was 1979. Because of unavailability of rainfall data (0.50 x 0.50) before 1971, the three time periods used in chapters 1 and 2 are not used in chapters 3 and 4, thus only one time period is used for rainfall and three temperatures (1971-204) and stream flow (1979-204). The analysis has shown the presence of regionally significant rends in the gridded data of annual mean temperature (Tmean) and winter Tmean over Tapi basin apart from significant trends found in regional time series of annual Tmean and winter Tmean of Tapi basin. Monthly, winter and pre- monsoon stream flow volume time series have also shown regionally significant trends over five gauging stations of Tapi basin. Main contributions of the trend detection analysis of hydro- climatic variables of Tapi basin are: 1) grid wise, regional scale and station wise trend detection of three temperatures, rainfall and stream flow respectively is performed, which was not done earlier, 2) regional significance evaluation of gridded data (rainfall and three temperatures) and station data of stream flow (five stream flow gauging stations) is performed, which was not done earlier, 3) all four aspects of trend of hydro-climatic variables are evaluated, which was not done earlier, 4) systematic trend detection study of gridded, regional and station data of hydro-climatic variables is performed in present study which was not done earlier. After detection of regionally significant trends, next step is finding the causal factors through attribution study. Once causal factors of climate change observed in given variable are found, then remedial measures can be carried out for minimizing the effect of these factors on climate change observed in given variable. There are three main methods of attribution found in literature viz. finger printing, optimal finger printing and artificial neural network (ANN) model. In finger printing method only the leading empirical orthogonal function (EOF) is used, so this method is conservative. In optimal finger printing, multivariate regression is used, which has certain assumptions which are difficult to be fulfilled in the case of climate studies as climate is essentially a non-linear dynamic system. ANN being non-linear in nature provides the required solution for the attribution problem related to climate. Attribution of regionally significant trends detected in monthly, winter and pre-monsoon stream flow volume time series of five gauging stations of Tape basin is not performed because five gauging stations were not representative of entire Tapi basin and two out of the five gauging stations have missing data greater than 15%. Number of significant monotonically increasing trends are more in winter gridded Tmean data as compared to annual gridded Tmean data. Thus attribution analysis of winter gridded Tmean data has given first priority followed by attribution of annual gridded Tmean data. ANN model is developed for the attribution of climate change observed in gridded data of winter Tmean and annual Tmean in three steps: 1) input variable selection (IVS) based on partial mutual information (PMI), 2) data splitting using k-means clustering method and Neyman allocation, 3) ANN model formulation by using best training algorithm among Levenberg-Marquardt (LM) algorithm, scaled conjugate gradient (SCG) algorithm and Broyden, Fletcher, Goldfarb, and Shano (BFGS) algorithm and optimum number of hidden neurons (varying from 1 to 3) corresponding to performance in terms of mean squared error (MSE) and to use these in final ANN model formulation with computation of performance evaluation measures (PEMs). Aforesaid third step is repeated for 50 iterations for each input forcing and given target output to minimize any random variation due to reinitialization of training algorithms. Also random variations due to initialization of ANN model are minimized by keeping initial weights and biases equal to zero. Final PEMs evaluated were the averages of 50 iterations as mentioned aforesaid. Target outputs used in two ANN attribution models are time series of regional winter Tmean and regional annual Tmean. Also in some cases of ANN model formulations, network parameters are kept less than number of data points in the training set for minimizing overriding. Inputs for ANN model were circulation indices and regional, global and national scale input variables. The inputs selected by PMI based input selection (PMIS) algorithm in the step of IVS of both ANN attribution models are seen to be subjected to natural and anthropogenic forcing, which undisputedly shows significant role of anthropogenic activities in observed climate change in aforesaid two gridded temperature variables. Also ranking of input forcing is performed in both the ANN attribution models according to their final PEM values. In the case of ANN attribution model for regional winter Tmean time series, dominant role of natural (‘nat’) input forcing is found behind the given climate change as compared to anthropogenic (‘anth’) input forcing. Among ‘anth’ inputs, effect of land cover (‘Landcover’) input forcing is found to be dominant as compared to green house gases (‘GHgases’) input forcing. Among ‘Landcover’ inputs, urban landcover input was found to be one of the important inputs. In the case of ANN attribution model for regional annual Tmean time series, dominant role of ‘anth’ input forcing is found behind the given climate change as compared to ‘nat’ input forcing. Among ‘anth’ inputs, there is dominant role of ‘Landcover’ input forcing as compared to ‘GHgases’ input forcing. Among ‘Landcover’ inputs, urban landcover input was found to be one of the important inputs. Contributions of attribution study are: 1) checking of input independence and significance by using PMI IVS method, which was not performed earlier, 2) division of data in such a way that al patterns of whole data are present in training, testing and validation subsets and the statistical properties of these subsets are similar to each other and to whole data, which was not performed earlier, 3) using LM, SCG and BFGS algorithms which are converging fatly as compared to Windrow-Hof algorithm and gradient descent algorithm. Also these three algorithms are les liable to be get stuck in local minima, 4) using land cover data as input forcing to ANN model used for attribution of climate change, which was not done earlier.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Dados sedimentológicos e hidrodinâmicos foram utilizados para estudar a dinâmica sedimentar da margem interna da restinga da Marambaia (baía de Sepetiba, Rio de Janeiro, SE Brasil). Foram realizadas três campanhas amostrais para coleta de sedimentos ao longo da restinga da Marambaia e na área submersa adjacente. Adicionalmente, em dezembro de 2013, três fundeios simultâneos para aquisição de dados hidrodinâmicos foram conduzidos paralelamente à restinga, ao longo da profundidade média de 6,5 metros. As medições abrangeram dois ciclos de maré (25 horas), incluindo perfilagem com CTDs, perfilagem correntométrica e coleta de amostras de água para determinação das concentrações do material particulado em suspensão. A partir do processamento das amostras de sedimentos em laboratório, foram obtidos os parâmetros estatísticos (média, desvio-padrão e assimetria) para o detalhamento da caracterização sedimentológica da área de estudo, bem como a aplicação de um modelo de tendência direcional de transporte de sedimentos (GisedTrend). A restinga apresenta areias médias e bem selecionadas, enquanto as amostras coletadas na porção submersa, em profundidades maiores que 2 m, passam de areias finas e bem selecionadas a siltes finos e mal selecionados em maiores profundidades. Quatro casos de tendência de transporte foram explorados em um total de 14 possibilidades e os mais significativos foram analisados com o intuito de identificar áreas de acumulação e remoção de sedimentos, podendo estar associados aos processos responsáveis pelo transporte de sedimentos, tais como correntes geradas pelos ventos locais, marés e dispersão de plumas de sedimentos em suspensão. Os dados hidrodinâmicos, durante o período amostrado, permitiram observar o complexo padrão de circulação existente, especialmente na área adjacente à área central da restinga. Dentre as observações realizadas, verificou-se a ocorrência de assimetria da maré, fato já documentado em trabalhos anteriores conduzidos próximo ao principal canal de acesso à baia, com períodos de enchente mais curtos e períodos de vazante mais longos. Diferentemente do que foi reportado nestes trabalhos, os períodos de vazante foram associados às correntes de maior intensidade. As concentrações de material particulado em suspensão situaram-se, em média, entre 10 e 20 mg/L tanto em superfície como próximo ao fundo; no entanto, suas variações temporais não apresentaram qualquer relação com as fases da maré. Possíveis áreas de convergência e divergência da circulação / células de transporte de sedimentos foram identificadas e comparadas aos vetores de tendência de transporte obtidos através do modelo GisedTrend, com resultados satisfatórios. / Sedimentological and hydrodynamic data sets have been used to study the sediment dynamics along the Marambaia barrier island bayside shoreline (Sepetiba bay, Rio de Janeiro state, SE Brazil). Three sampling campaigns were carried out to collect surface sediment samples along the barrier island and on the nearby submersed area. Additionally, in December 2013, hydrodynamic measurements were simultaneously conducted at three anchor stations positioned parallel to the barrier island, roughly along the 6.5 m isobath. The measurements, that spanned two full tidal cycles (25 hours), included water column profiling with CTDs, water column current profiling, and water column sampling to determine suspended-sediment concentrations. Once the sediment samples had been processed in the laboratory, statistical parameters (mean, sorting and skewness) were computed, allowing the thoroughful sedimentological characterization of the study area as well as the application of a grain-size trend analysis model (GisedTrend) to determine sediment transport trend vectors. The barrier island is chiefly made up of medium, well-sorted sands grading to fine, well-sorted sands and fine, poorly-sorted silts at greater depths. Four trend cases out of the 14 possibilities were explored and the most significant were further analyzed in order to identify areas of sediment accumulation or removal, and then be associated with the possible physical processes responsible for sediment transport, such as tidal currents, wind-generated currents and dispersal of sediment plumes. Hydrodynamic data documented that, over the time scale of the measurements, the water column circulation is highly complex, especially in the area adjacent to the center of the barrier island. As already verified in the area close to the main navigational channel, tidal asymmetry was documented, with floods being shorter than ebbs. However, contrarily to these previous observations, ebb currents were stronger than flood currents. Mean suspended-sediment concentrations (SSC) ranged between 10 and 20 mg/L both close to the surface and the nearbed area; yet, no relationship between SSC temporal variability and tidal stage could be identified. Possible convergence and divergence circulation / sediment transport cells were identified and compared to the GisedTrend output, with satisfactory results.

Cette thèse se situe à la confluence des domaines de "la modélisation de thématiques" (topic modeling) et l'"analyse d'opinions" (opinion mining). Le problème que nous traitons est la modélisation conjointe et dynamique des thématiques (sujets) et des opinions (prises de position) sur le Web et les médias sociaux. En effet, dans la littérature, ce problème est souvent décomposé en sous-tâches qui sont menées séparément. Ceci ne permet pas de prendre en compte les associations et les interactions entre les opinions et les thématiques sur lesquelles portent ces opinions (cibles). Dans cette thèse, nous nous intéressons à la modélisation conjointe et dynamique qui permet d'intégrer trois dimensions du texte (thématiques, opinions et temps). Afin d'y parvenir, nous adoptons une approche statistique, plus précisément, une approche basée sur les modèles de thématiques probabilistes (topic models). Nos principales contributions peuvent être résumées en deux points : 1. Le modèle TS (Topic-Sentiment model) : un nouveau modèle probabiliste qui permet une modélisation conjointe des thématiques et des opinions. Ce modèle permet de caractériser les distributions d'opinion relativement aux thématiques. L'objectif est d'estimer, à partir d'une collection de documents, dans quelles proportions d'opinion les thématiques sont traitées. 2. Le modèle TTS (Time-aware Topic-Sentiment model) : un nouveau modèle probabiliste pour caractériser l'évolution temporelle des thématiques et des opinions. En s'appuyant sur l'information temporelle (date de création de documents), le modèle TTS permet de caractériser l'évolution des thématiques et des opinions quantitativement, c'est-à-dire en terme de la variation du volume de données à travers le temps. Par ailleurs, nous apportons deux autres contributions : une nouvelle mesure pour évaluer et comparer les méthodes d'extraction de thématiques, ainsi qu'une nouvelle méthode hybride pour le classement d'opinions basée sur une combinaison de l'apprentissage automatique supervisé et la connaissance a priori. Toutes les méthodes proposées sont testées sur des données réelles en utilisant des évaluations adaptées. / This work is located at the junction of two domains : topic modeling and sentiment analysis. The problem that we propose to tackle is the joint and dynamic modeling of topics (subjects) and sentiments (opinions) on the Web. In the literature, the task is usually divided into sub-tasks that are treated separately. The models that operate this way fail to capture the topic-sentiment interaction and association. In this work, we propose a joint modeling of topics and sentiments, by taking into account associations between them. We are also interested in the dynamics of topic-sentiment associations. To this end, we adopt a statistical approach based on the probabilistic topic models. Our main contributions can be summarized in two points : 1. TS (Topic-Sentiment model) : a new probabilistic topic model for the joint extraction of topics and sentiments. This model allows to characterize the extracted topics with distributions over the sentiment polarities. The goal is to discover the sentiment proportions specfic to each of theextracted topics. 2. TTS (Time-aware Topic-Sentiment model) : a new probabilistic model to caracterize the topic-sentiment dynamics. Relying on the document's time information, TTS allows to characterize the quantitative evolutionfor each of the extracted topic-sentiment pairs. We also present two other contributions : a new evaluation framework for measuring the performance of topic-extraction methods, and a new hybrid method for sentiment detection and classification from text. This method is based on combining supervised machine learning and prior knowledge. All of the proposed methods are tested on real-world data based on adapted evaluation frameworks.

The objective of this study is to investigate land-use changes and water quality trends within the headwaters of the Alafia River watershed. Water quality data were obtained from the Environmental Protection Commission of Hillsborough County (EPCHC). Eleven water quality parameters selected for analysis included: temperature (˚C), dissolved oxygen (DO), percent saturation of DO, conductivity, pH, total phosphorous (TP), total nitrogen (TN), ammonium, chlorophyll-a (uncorrected), fecal coliforms, and enterococci. ArcMap® & SWFWMD data were used to map EPCHC sampling stations, calculate contributing watershed size, and determine land-use changes over the course of the sampling period; 17 stations were chosen for this study. The annual average for each of the water quality parameters was calculated along with a Mann-Kendall Trend Analysis in order to determine if any of the observed trends were statistically significant. A non-parametric Kendall’s tau-b correlation and stepwise multiple linear regression tests were conducted in SPSS to determine if any statistically significant relationships between water quality data, land-use and basin size exist. The land-use results showed every basin consisted of some percentage of Low Density Residential, Cropland & Pastureland, Reservoirs, and Streams & Lake Swamps. In addition, no basin comprised of more than 20% wetlands and often it appears urbanization was at the sacrifice of agricultural lands, as opposed to wetlands. The trends in water quality showed eight of the 17 basins had at least one statistically significant trend. Analysis of the data used for this study has shown instances where water quality measurements were in violation of state standards. Changes in water quality can be statistically related to changes in land-use and basin size as both the correlation and the regression showed consistent relationships between several LULC types and water quality parameters: increases in Commercial & Services causes increased nutrients (TP and TN); Cropland & Pastureland causes decreased DO and DO% Saturation; increases in Tree Crops causes a decrease in pH; increasing Other Open Lands Rural causes a decrease in temperature; and increases in Shrub & Brushland cause decreases in conductivity and pH. As these relationships are based on the results from both analyses, it would seem that these relationships are the most reliable, and are key results of the study. These key relationships might be areas that future water resource managers may want to focus on in order to more efficiently improve or regulate water quality within headwater streams.